Who wants you to be afraid of short sleep like a Big Bad Wolf? Follow the money.
Manufacturers of sleeping pills provided most of the initial funding for The National Sleep Foundation (NSF), an organization devoted largely to issuing public proclamations about sleep. A public relations firm for the makers of Ambien bragged on the internet about their role in a NSF campaign "to raise insomnia to its deserved level of a national public health crisis." Directed in part by agents of the Ambien manufacturer, this campaign was successful in increasing new prescriptions for sleep medications. Ambien attained 30 percent of the sales in the first year. Later, NSF campaigns about alleged dangers of insufficient sleep in children were followed by a huge increase in sleeping pill consumption by children.
The NSF was founded in part by the American Academy of Sleep Medicine (AASM), an organization of sleep clinic clinicians interested in promoting their specialty. In 2005, the President of the AASM discussed marketing efforts of the organization, saying "an initial focus of the campaign will be insomnia and its consequences. In the next several years, we will witness the launches of several new hypnotic medications, and, with those launches, an unprecedented amount of direct-to-consumer advertising from the pharmaceutical industry. It is our belief that we can use this development to our advantage. . . We will partner with a consortium of industry, from which we anticipate (and have already received) considerable financial support." Even among doctors, much of the money for crying wolf about short sleep has come from sleeping pill manufacturers.
What are the real risks of short sleep? Would you think that mortality risks versus survival might be good measures? An excellent new analysis of 25 selected studies from around the world showed that people reporting 7 hours sleep had the lowest mortality. Those reporting only 4 or 5 hours sleep at night had a very small 4-7% increases in mortality compared to 7 hours, whereas those reporting 6 hours had no significant difference in survival from 7 hours. In the longer sleep direction, those reporting 8 hours sleep had 7% higher mortality than those sleeping 7 hours, and those reporting 9 or 10 hours had 21% or 37% increased mortality. No significant mortality elevation was found among those with short sleep in Asia, only in the U.S.A., indicating that the small association of short sleep with elevated mortality in the U.S. might be due to social factors, not biology. Since the currently-reported average sleep duration in the U.S. is somewhere around 6-7 hours, the U.S. average is roughly ideal for survival. Moreover, since there tend to be more people reporting sleep longer than 7 hours than shorter than 6 hours, and there is a higher mortality risk with long sleep, the long sleep problem is a much larger problem than the short sleep problem. An independent analysis of 27 studies of people age 60 or over had similar findings, and also observed that cardiovascular mortality was significantly associated with long sleep but not with short sleep.
You might wonder why for over 20 years the NSF has been advising adults to sleep 8 hours, when those who sleep 6-7 hours live longer and suffer less cardiovascular deaths. Could it be that crying wolf about long sleep might not sell sleeping pills as well as fear of short sleep? You might wonder why the AASM issued a statement recommending against sleeping less than 7 hours, at the same time claiming that it was uncertain whether sleeping 9 hours or more was associated with mortality risk. As the recent reports along with many older reports prove, the risks associated with long sleep are not uncertain at all. To make it harder to follow the money, in their initial report, the AASM authors overlooked their journal's requirement to report if they were receiving money from sleeping pill companies. Correcting this, they still failed to mention how much the AASM itself was receiving. I can now tell you that several AASM authors of their recommended sleep duration had financial relations with sleeping pill manufacturers. At about the same time, the American Thoracic Society issued a true statement that both long sleep and short sleep were related to increased mortality, but those authors did not report any payments from hypnotics manufacturers. If you are wondering if drug company money could influence the health advice of scientists, there is plenty of evidence that it does. The difference between the conclusions of the AASM and the American Thoracic Society looks like an example.
If you worry about short sleep, do NOT take sleeping pills. Worldwide, there have now been 40 epidemiologic studies of the mortality risks associated with taking sleeping pills, of which 39 showed that people taking sleeping pills died sooner. It has been proven that sleeping pills cause depressions and infections. The real national public health crisis has been a huge increase in overdose deaths, many from combinations of sleeping pills with opiates, resulting from rapid increases in both sleeping pill and opiate prescriptions in the last decade or two. The weight of evidence is that sleeping pills also cause cancer, but there are not enough data to be certain.
To my knowledge, there has never (ever) been a single randomized clinical trial giving objective evidence that a U.S.-approved sleeping pill helps an insomnia patient perform better the next day or produces any objective improvement in general health. There are dozens of studies showing that patients randomly given sleeping pills are sleepier the next day and perform objectively worse than those randomly given placeboes. Incidentally, many nice doctors who have received funding from sleeping pill manufacturers have been making a fuss about associations of short sleep with obesity and diabetes. Most of this is baloney. In any case, after many dozens of clinical trials of sleeping pills, I have found no reports that taking sleeping pills ever helps obese people to lose weight.
It turns out that a lot of what determines how long a person sleeps is genetic. Nobody knows what to do about that genetic influence, if anything. There is essentially no evidence that a natural short sleeper who tries to sleep more will be healthier, or even that a natural short sleeper can increase their sleep much. There is better evidence that people accustomed to long sleep can shorten their sleep without evident consequences, though we are not sure yet if it does much good.
All this said, there are indeed some people whose work restricts their sleep too much. Some years ago, a Navy research submarine sank in San Diego Bay. The sailor court martialed for this accident said his commander had allowed him only a few hours sleep per night for weeks, but his commander testified that allowing only a few hours sleep per 24 hours was routine on nuclear submarines. I would prefer that the sailors who make decisions that can start nuclear wars be permitted plenty of sleep. A friend of mine who flew combat missions over Kosovo said the missions were so long that he would sometimes fall asleep in the pilot's seat over the combat zone. Fortunately, nothing bad happened to him. It is well known that the schedules of airline pilots can be so difficult that they fall asleep in the cockpit. I would prefer that pilots got better sleep. Many long distance truckers drive those huge rigs on only 4-5 hours sleep in 24 hours. We would all be safer if they slept more. A fair number of automobile accidents are thought to be due to falling asleep at the wheel, but much of this occurs among single young men who have stayed up too late at night partying. Such automobile accidents may be more due to driving at the wrong time for a person's body clock than from curtailment of sleep: people who stay up all night often become more alert when morning arrives, even as their sleep loss becomes more prolonged.
I am skeptical that the average American adult who regularly sleeps 6 or 6 ½ hours is measurably impaired in every-day life. Consider that people who have jobs tend to sleep less than people who can't keep a job. That does not prove that short sleep helps people do the job better, but at least it should reassure some working folks. Highly controlled laboratory studies that keep participants away from daylight and caffeine can demonstrate that people perform extremely boring tasks less reliably when they have slept less than 8 hours. I do not know of any well-controlled randomized long-term trials that show that people who sleep 6.5 hours perform worse than those who sleep 8 hours in everyday life. We have reviewed that 8-hour sleepers are NOT healthier on average.
To conclude, when you hear somebody crying wolf about short sleep, ask who is paying them and the people from whom they get their information. In contrast, I do not cry wolf about a person who really sleeps a long time, because there is no sufficient proof that anything useful can be done unless there are specific medical causes. On the other hand, a person who spends over 8 hours in bed and is concerned about being awake over an hour and a quarter of that time will probably feel better if that person spends less time in bed. Cognitive-behavioral therapy explains in detail what to do about spending too long in bed for those who have insomnia. The sleep clinic doctors could earn more if they would learn how to care for the people who spend too long in bed.
(1) Kripke DF. Chronic hypnotic use: Deadly risks, doubtful benefit. Sleep Medicine Reviews 2000; 4(1):5-20.
(2) Sateia MJ. Editorial: Increasing Public Awareness. J Clin Sleep Med 2005; 1(2):117-118.
(3) Shen X, Wu Y, Zhang D. Nighttime sleep duration, 24-hour sleep duration and risk of all-cause mortality among adults: a meta-analysis of prospective cohort studies. Sci Rep 2016; 6:21480.
(4) Silva AA, Mello RG, Schaan CW, Fuchs FD, Redline S, Fuchs SC. Sleep duration and mortality in the elderly: a systematic review with meta-analysis. BMJ Open 2016; 6(2):e008119.
Dr. Kripke has studied the health of people with different sleep durations among over 2 million participants in American Cancer Society studies. More information is available at his non-profit web site, www.DarkSideOfSleepingPills.com.